The journal of pain : official journal of the American Pain Society
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Herpes zoster causes substantial morbidity, especially among older adults. Although the acute cutaneous manifestations can be painful and troublesome, the most important consequence of herpes zoster (shingles) is the chronic pain syndrome known as postherpetic neuralgia (PHN). Previous studies have suggested that declining varicella-zoster virus (VZV)-specific cell-mediated immune (CMI) responses account for the increased frequency of herpes zoster seen in older adults. This led to the idea that immunization designed to boost VZV-specific CMI responses might reduce the risk of herpes zoster. This hypothesis was tested in a large, randomized, placebo-controlled clinical trial called the Shingles Prevention Study (SPS). Compared with the placebo group, herpes zoster vaccine recipients had a 61.1% reduction in zoster "burden of illness" (an index incorporating incidence and severity of herpes zoster); a 66.5% reduction in the incidence of postherpetic neuralgia; and a 51.3% reduction in the incidence of herpes zoster. The incidence of serious adverse events was not different between the overall vaccine and placebo populations. The most frequently encountered adverse event among vaccine recipients was local reactogenicity, with self-limited and generally mild tenderness, warmth, or erythema occurring at the injection site in about one-half of vaccine recipients. The zoster vaccine was approved by the US Food and Drug Administration in 2006 and is indicated for prevention of herpes zoster in immunocompetent persons aged 60 years and older. ⋯ The herpes zoster vaccine provides physicians with an effective means for reducing a patient's risk for developing shingles and its attendant complications. No significant safety concerns regarding the vaccine have been identified. Indications for use of the attenuated-virus vaccine in special subpopulations continue to evolve.
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Review
A review of objective pain measures for use with critical care adult patients unable to self-report.
Critically ill patients experience significant levels of pain and discomfort from multiple intrinsic and extrinsic sources while in the intensive care unit (ICU). The use of objective pain measures in nonverbal patients is an essential alternative approach for pain assessment when self-reports are unavailable. This paper provides a critical review of the psychometric properties of 6 objective pain measures that were developed to assess pain in nonverbal adult patients in the ICU. The strengths and weaknesses of these objective measures are evaluated, as well as their applicability for use with this patient population. Although 2 of the 6 objective pain measures showed good evidence of validity and reliability, none has undergone vigorous validation or has been accepted as a standardized measure. Findings from the available studies of objective pain measures provide useful information to direct future research to develop and validate clinically useful pain measures for use with critically ill patients unable to self-report. ⋯ This review provides clinicians with a summary of the psychometric properties of 6 objective pain measures and discusses their applicability for use to assess pain in critically ill adult patients unable to self-report.
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Accurate evaluation of pain plays a critical role in identifying new interventions for the treatment and prevention of herpes zoster and postherpetic neuralgia (PHN). Different types of pain and other sensory symptoms are found in patients with herpes zoster, and these vary greatly with respect to their presence, location, duration, intensity, and quality. The results of recent studies of herpes zoster and PHN and the development of new methods for assessing neuropathic pain provide a foundation for diagnosing and assessing the pain associated with herpes zoster. We review the results of recent research to identify the essential components that must be considered in developing an evidence-based description of pain associated with herpes zoster and PHN. ⋯ Comprehensive assessments of pain are necessary for clinical research on the epidemiology, natural history, pathophysiologic mechanisms, treatment, and prevention of pain in herpes zoster and PHN.
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Comparative Study
Neuromodulation of thoracic intraspinal visceroreceptive transmission by electrical stimulation of spinal dorsal column and somatic afferents in rats.
Clinical studies have shown that neuromodulation therapies, such as spinal cord stimulation (SCS) and transcutaneous electrical nerve stimulation (TENS), reduce symptoms of chronic neuropathic and visceral pain. The neural mechanisms underlying SCS and TENS therapy are poorly understood. The present study was designed to compare the effects of SCS and TENS on spinal neuronal responses to noxious stimuli applied to the heart and esophagus. Direct stimulation of an intercostal nerve (ICNS) was used to simulate the effects of TENS. Extracellular potentials of left thoracic (T3) spinal neurons were recorded in pentobarbital anesthetized, paralyzed, and ventilated male rats. SCS (50 Hz, 0.2 ms, 3-5 minutes) at a clinical relevant intensity (90% of motor threshold) was applied on the C1-C2 or C8-T1 ipsilateral spinal segments. Intercostal nerve stimulation (ICNS) at T3 spinal level was performed using the same parameters as SCS. Intrapericardial injection of bradykinin (IB, 10 microg/mL, 0.2 mL, 1 minute) was used as the noxious cardiac stimulus. Noxious thoracic esophageal distension (ED, 0.4 mL, 20 seconds) was produced by water inflation of a latex balloon. C1-C2 SCS suppressed excitatory responses of 16/22 T3 spinal neurons to IB and 25/30 neurons to ED. C8-T1 SCS suppressed excitatory responses of 10/15 spinal neurons to IB and 17/23 neurons to ED. ICNS suppressed excitatory responses of 9/12 spinal neurons to IB and 17/22 neurons to ED. These data showed that SCS and ICNS modulated excitatory responses of T3 spinal neurons to noxious stimulation of the heart and esophagus. ⋯ Neuromodulation of noxious cardiac and esophageal inputs onto thoracic spinal neurons by spinal cord and intercostal nerves stimulation observed in the present study may help account for therapeutic effects on thoracic visceral pain by activating the spinal dorsal column or somatic afferents.
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Comparative Study
Metoclopramide versus hydromorphone for the emergency department treatment of migraine headache.
We conducted a retrospective cohort study to compare the effects of metoclopramide versus hydromorphone for the initial emergency department treatment of migraine headache at an urban teaching hospital. The primary outcome measure was the mean difference in the subjects' self-reported pain scores before and after the administration of the initial medication treatment. We also estimated crude and adjusted relative risks (using Poisson multivariate regression modeling) to assess and control potential confounding by age, gender, race, and pain score before initial medication. Two hundred subjects were included, with 51 (25.5%) receiving intravenous or intramuscular hydromorphone, 95 (47.5%) receiving intravenous metoclopramide, and 54 (27.0%) receiving 1 of several other medications. Using a standardized pain scale of 0 to 10, mean pain score reductions were 2.3 points for hydromorphone, 3.7 points for metoclopramide, and 2.8 points for all other medications combined (P < .001). When comparing metoclopramide versus hydromorphone, the crude relative risk for pain reduction of 3 or more points was 1.76 (95% CI, 1.12-2.75, P = .01), and the adjusted relative risk was 1.60 (95% CI, 0.84-3.03, P = .15). Metoclopramide also resulted in less use of rescue medications, faster times to discharge, and no difference in the frequency of adverse reactions. ⋯ Metoclopramide appears to be an effective initial medical treatment for migraine headaches in the emergency department setting, but its pharmacologic mechanism remains incompletely understood. A double-blinded, randomized, controlled trial comparing standard dosages of hydromorphone versus metoclopramide will be needed to definitively determine which medication is more effective.